That's... hacky... Is it not possible to add the ammo to the unit list and put the descriptions in there? It IS possible for ammos to be added to the unit list. The orbital rockets are considered ammo and are in there.
They did add the descriptions to the json recently, but the live_game hacks are still there, so it's not quite finished yet.
Grep is your friend. It will help with many of the things you're likely to do with modding. On windows one way to get it is install cygwin.